package com.threecloud.dataserviceyy.util;

import com.alibaba.fastjson2.JSON;
import com.alibaba.fastjson2.JSONArray;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.Map;

/**
 * VAA录音盒HTTP工具类
 * 用于与录音盒设备进行HTTP通信
 * 参考文档: ebox_developer_guide.html (EBOX-8108 电话录音仪开发手册)
 */
@Component
public class VaaHttpUtil {

    private static final Logger logger = LoggerFactory.getLogger(VaaHttpUtil.class);

    /** 连接超时：30秒，设备可能在远端网络 */
    private static final int CONNECT_TIMEOUT = 30000;
    /** API读取超时：60秒 */
    private static final int READ_TIMEOUT = 60000;
    /** 文件下载读取超时：5分钟，音频文件可能较大 */
    private static final int DOWNLOAD_READ_TIMEOUT = 300000;
    /** 重试次数 */
    private static final int MAX_RETRY = 3;
    /** 重试间隔基数（毫秒） */
    private static final int RETRY_BASE_DELAY = 2000;

    /**
     * HTTP登录认证
     * @param loginUrl 登录URL，例如：http://192.168.1.100/authorize?username=admin&password=admin123
     * @return 登录成功后返回Authorization Cookie值
     */
    public String httpLogin(String loginUrl) throws Exception {
        return executeWithRetry(() -> {
            logger.debug("正在登录录音盒: {}", loginUrl);

            HttpURLConnection conn = null;
            try {
                URL url = new URL(loginUrl);
                conn = (HttpURLConnection) url.openConnection();
                conn.setInstanceFollowRedirects(false);
                conn.setConnectTimeout(CONNECT_TIMEOUT);
                conn.setReadTimeout(READ_TIMEOUT);
                conn.setRequestMethod("GET");

                int responseCode = conn.getResponseCode();
                if (responseCode == HttpURLConnection.HTTP_OK || responseCode == HttpURLConnection.HTTP_MOVED_TEMP) {
                    String authorization = getAuthorizationCookie(conn);
                    if (authorization == null || authorization.isEmpty()) {
                        throw new RuntimeException("登录失败，录音盒未返回Authorization Cookie");
                    }
                    logger.info("录音盒登录成功");
                    return authorization;
                }
                throw new RuntimeException("登录失败，HTTP状态码: " + responseCode);
            } finally {
                if (conn != null) {
                    conn.disconnect();
                }
            }
        }, "登录");
    }

    /**
     * HTTP访问API获取数据
     * @param apiUrl API地址，例如：http://192.168.1.100/service/running/channel
     * @param authorization 登录后返回的Authorization Cookie值
     * @return 返回JSON字符串
     */
    public String httpVisit(String apiUrl, String authorization) throws Exception {
        return executeWithRetry(() -> {
            logger.debug("访问API: {}", apiUrl);

            HttpURLConnection conn = null;
            try {
                URL url = new URL(apiUrl);
                conn = (HttpURLConnection) url.openConnection();
                conn.setConnectTimeout(CONNECT_TIMEOUT);
                conn.setReadTimeout(READ_TIMEOUT);
                conn.setRequestMethod("GET");
                addAuthorization(conn, authorization);

                int responseCode = conn.getResponseCode();
                if (responseCode == 200) {
                    BufferedReader reader = new BufferedReader(
                        new InputStreamReader(conn.getInputStream(), "UTF-8")
                    );
                    StringBuilder result = new StringBuilder();
                    String line;
                    while ((line = reader.readLine()) != null) {
                        result.append(line);
                    }
                    reader.close();

                    String jsonResult = result.toString();
                    logger.debug("API响应: {}", jsonResult);
                    if (isLoginPage(jsonResult)) {
                        throw new RuntimeException("录音盒认证失效，返回登录页面");
                    }
                    return jsonResult;
                } else {
                    throw new RuntimeException("API访问失败，HTTP状态码: " + responseCode);
                }
            } finally {
                if (conn != null) {
                    conn.disconnect();
                }
            }
        }, "API访问");
    }

    /**
     * 下载录音文件（带重试）
     * @param fileUrl 文件URL，例如：http://192.168.1.100/record/2026/05/20/OUT-xxx.wav
     * @param savePath 保存路径
     * @param authorization 登录后返回的Authorization Cookie值
     */
    public void httpDown(String fileUrl, String savePath, String authorization) throws Exception {
        executeWithRetry(() -> {
            logger.info("开始下载录音文件: {} -> {}", fileUrl, savePath);

            // 确保目录存在
            File saveFile = new File(savePath);
            if (!saveFile.getParentFile().exists()) {
                saveFile.getParentFile().mkdirs();
            }

            HttpURLConnection conn = null;
            InputStream inputStream = null;
            FileOutputStream outputStream = null;

            try {
                URL url = new URL(fileUrl);
                conn = (HttpURLConnection) url.openConnection();
                conn.setConnectTimeout(CONNECT_TIMEOUT);
                conn.setReadTimeout(DOWNLOAD_READ_TIMEOUT);
                conn.setRequestMethod("GET");
                addAuthorization(conn, authorization);

                int responseCode = conn.getResponseCode();
                if (responseCode == 200) {
                    inputStream = conn.getInputStream();
                    outputStream = new FileOutputStream(savePath);

                    byte[] buffer = new byte[8192];
                    int bytesRead;
                    long totalBytes = 0;
                    long lastLogTime = System.currentTimeMillis();

                    while ((bytesRead = inputStream.read(buffer)) != -1) {
                        outputStream.write(buffer, 0, bytesRead);
                        totalBytes += bytesRead;
                        // 每10秒打印一次进度
                        long now = System.currentTimeMillis();
                        if (now - lastLogTime > 10000) {
                            logger.info("下载进度: {} MB", totalBytes / 1024 / 1024);
                            lastLogTime = now;
                        }
                    }

                    outputStream.flush();
                    logger.info("录音文件下载完成: {}, 大小: {} bytes ({} MB)",
                            savePath, totalBytes, totalBytes / 1024 / 1024);
                } else {
                    throw new RuntimeException("文件下载失败，HTTP状态码: " + responseCode);
                }
            } finally {
                closeQuietly(inputStream);
                closeQuietly(outputStream);
                if (conn != null) {
                    conn.disconnect();
                }
            }
            return null;
        }, "文件下载");
    }

    /**
     * 带重试的执行器
     */
    private <T> T executeWithRetry(RetryableTask<T> task, String operationName) throws Exception {
        Exception lastException = null;
        for (int attempt = 1; attempt <= MAX_RETRY; attempt++) {
            try {
                return task.execute();
            } catch (java.net.SocketTimeoutException e) {
                lastException = e;
                if (attempt < MAX_RETRY) {
                    long delay = RETRY_BASE_DELAY * attempt;
                    logger.warn("{}(第{}次)超时，{}ms后重试: {}", operationName, attempt, delay, e.getMessage());
                    Thread.sleep(delay);
                }
            } catch (java.net.ConnectException e) {
                lastException = e;
                if (attempt < MAX_RETRY) {
                    long delay = RETRY_BASE_DELAY * attempt;
                    logger.warn("{}(第{}次)连接失败，{}ms后重试: {}", operationName, attempt, delay, e.getMessage());
                    Thread.sleep(delay);
                }
            } catch (IOException e) {
                lastException = e;
                if (attempt < MAX_RETRY && isRetryable(e)) {
                    long delay = RETRY_BASE_DELAY * attempt;
                    logger.warn("{}(第{}次)IO异常，{}ms后重试: {}", operationName, attempt, delay, e.getMessage());
                    Thread.sleep(delay);
                } else {
                    throw e;
                }
            }
        }
        throw new RuntimeException(operationName + "失败，已重试" + MAX_RETRY + "次", lastException);
    }

    private boolean isRetryable(IOException e) {
        String msg = e.getMessage();
        if (msg == null) return false;
        return msg.contains("timed out") || msg.contains("connection") || msg.contains("reset");
    }

    @FunctionalInterface
    private interface RetryableTask<T> {
        T execute() throws Exception;
    }

    private void closeQuietly(Closeable c) {
        if (c != null) {
            try { c.close(); } catch (IOException ignored) {}
        }
    }

    private void addAuthorization(HttpURLConnection conn, String authorization) {
        if (authorization != null && !authorization.isEmpty()) {
            conn.setRequestProperty("Cookie", "Authorization=" + authorization);
        }
    }

    private boolean isLoginPage(String responseBody) {
        if (responseBody == null) {
            return false;
        }
        String body = responseBody.trim().toLowerCase();
        return body.startsWith("<!doctype") || body.startsWith("<html")
                || (body.contains("<form") && body.contains("password"));
    }

    private String getAuthorizationCookie(HttpURLConnection conn) {
        for (Map.Entry<String, List<String>> entry : conn.getHeaderFields().entrySet()) {
            if (entry.getKey() == null || !"Set-Cookie".equalsIgnoreCase(entry.getKey())) {
                continue;
            }
            String authorization = getAuthorizationValue(entry.getValue());
            if (authorization != null && !authorization.isEmpty()) {
                return authorization;
            }
        }
        return null;
    }

    private String getAuthorizationValue(List<String> cookies) {
        if (cookies == null || cookies.isEmpty()) {
            return null;
        }
        for (String cookie : cookies) {
            String prefix = "Authorization=";
            int start = cookie.indexOf(prefix);
            if (start < 0) {
                continue;
            }
            start += prefix.length();
            int end = cookie.indexOf(';', start);
            return end >= 0 ? cookie.substring(start, end) : cookie.substring(start);
        }
        return null;
    }

    /**
     * 解析通道状态JSON
     */
    public JSONArray parseChannelData(String jsonData) {
        if (jsonData == null || jsonData.isEmpty() || "[]".equals(jsonData)) {
            return new JSONArray();
        }
        return JSON.parseArray(jsonData);
    }

    /**
     * 解析录音记录JSON
     */
    public JSONArray parseRecordData(String jsonData) {
        if (jsonData == null || jsonData.isEmpty() || "[]".equals(jsonData)) {
            return new JSONArray();
        }
        return JSON.parseArray(jsonData);
    }

    /**
     * 获取分机号码配置
     * EBOX接口: GET /service/ext/number
     * 返回每条线路的分机号码，如: {"1":"8001","2":"8002",...}
     * @param extUrl 接口地址，例如：http://192.168.1.100/service/ext/number
     * @param authorization 登录后返回的Authorization Cookie值
     * @return 通道-分机号映射 Map<channel, phoneNumber>
     */
    public Map<String, String> getExtensionNumbers(String extUrl, String authorization) throws Exception {
        String jsonData = httpVisit(extUrl, authorization);
        if (jsonData == null || jsonData.isEmpty() || "[]".equals(jsonData) || "{}".equals(jsonData)) {
            return new java.util.HashMap<>();
        }
        try {
            // EBOX返回的是JSON对象，key是通道号(1-8)，value是分机号码
            com.alibaba.fastjson2.JSONObject jsonObj = JSON.parseObject(jsonData);
            Map<String, String> result = new java.util.HashMap<>();
            for (String key : jsonObj.keySet()) {
                String value = jsonObj.getString(key);
                result.put(key, value != null ? value : "");
            }
            logger.info("获取到分机号码配置: {} 条", result.size());
            return result;
        } catch (Exception e) {
            logger.warn("解析分机号码配置失败: {}", e.getMessage());
            return new java.util.HashMap<>();
        }
    }
}